  <template>
    <div>
      <div class="goods">
        <div class="menu-wrapper" ref="menuWrapper">
          <ul>
            <li class="menu-item " :class="{current:currentleft==index}" v-for="(good , index) in shopGoods" :key="index"
              @click="changeLeft(index)"
            >
              <span class="text bottom-border-1px">
              <img class="icon" src="https://fuss10.elemecdn.com/0/6a/05b267f338acfeb8bd682d16e836dpng.png">
              {{good.name}}
              </span>
            </li>
          </ul>
        </div>
        <div class="foods-wrapper">
          <ul ref="foodsWrapper">
            <li class="food-list food-list-hook" v-for="(good , index ) in shopGoods" :key="index">
              <h1 class="title">{{good.name}}</h1>
              <ul>
                <li class="food-item bottom-border-1px" v-for="(food , index ) in good.foods"
                    :key="index" @click="showFoodBigImg(food)">
                  <div class="icon">
                    <img width="57" height="57"
                         :src="food.icon">
                  </div>
                  <div class="content">
                    <h2 class="name">{{food.name}}</h2>
                    <p class="desc">{{food.description}}</p>
                    <div class="extra">
                      <span class="count">月售 {{food.sellCount}} 份</span>
                      <span>好评率 {{food.rating}}%</span></div>
                    <div class="price">
                      <span class="now">￥{{food.price}}</span>
                    </div>
                    <div class="cartcontrol-wrapper">
                      <CartControl :food="food"/>
                    </div>
                  </div>
                </li>

              </ul>
            </li>
          </ul>
        </div>
        <shopCar></shopCar>
      </div>
      <FoodPop :food="clickFood" ref="clickFood"/>
    </div>
  </template>

  <script>
    import {mapState} from 'vuex'
    import BScroll from "better-scroll"
    import $ from "jquery"
    import CartControl from "../../../components/cartControl/cartControl"
    import FoodPop from "../../../components/foodPop/foodPop"
    import ShopCar from "../../../components/ShopCar/ShopCar"

    export default {
      name: "ShopGoods",
      data () {
        return {
          tops:[],
          scrollY:0,
          clickFood:{}
        }
      },
      computed : {
        ...mapState(['shopGoods']),
        currentleft(){
          return this.tops.findIndex((item,index) =>{
            return this.scrollY>=this.tops[index]&&this.scrollY<=this.tops[index+1]
          })
        }
      },
      mounted() {
        this.$store.dispatch('reqShopGoods', () => {
          this.$nextTick(() => {
            this.menuwrapper = new BScroll('.menu-wrapper', {
              click: true
            })
            this.foodswrapper = new BScroll('.foods-wrapper', {
              probeType: 2, // 手指滑动(惯性滑动和编码滑动不监视)
              click: true
            })
            // 监听滑动
            this.foodswrapper.on('scroll', ({x, y}) => {
              console.log(x, y)
              this.scrollY = Math.abs(y)
            })
            // 监视滑动结束
            this.foodswrapper.on('scrollEnd', (pos) => {
              console.log('滑动结束', pos.y)
              this.scrollY = Math.abs(pos.y) // 解决惯性滑动更新
            })


            const tops = []
            let top = 0
            /*// 得到 ul 下所有的子 li
            const lis = this.$refs.foodsWrapper.getElementsByClassName('food-list-hook')
            Array.prototype.slice.call(lis).forEach((li, index) => {
              top += li.clientHeight
              tops.push(top)
            })
            // 保存 tops
            this.tops = tops
            console.log(this.tops)*/
            // 计算各个 top, 并保存到 tops
            tops.push(top)
            let lis = $(this.$refs.foodsWrapper).find('.food-list-hook');
            lis=Array.from(lis);
            lis.forEach((item)=>{
              top+=item.clientHeight
              tops.push(top)
            })
            console.log(tops)
            // 保存 tops
            this.tops = tops
          })
        })
      },
      methods:{
        changeLeft(index){
          // this.currentleft=index;
          // 得到滚动目标坐标
          const top = this.tops[index]+5
          console.log(this.tops[index])
          // 更新目标 scrollY 值
          this.scrollY = top
          // 平滑滚动到指定位置
          this.foodswrapper.scrollTo(0, -top, 300)
        },
        showFoodBigImg (food) {
          this.clickFood=food;
          this.$refs.clickFood.isShow=true;
        }
      },
      components:{
        CartControl,
        FoodPop,
        ShopCar
      }

    }
  </script>

  <style lang="stylus" rel="stylesheet/stylus">
    @import "../../../common/stylus/mixins.styl"
    .goods
      display:flex
      position:absolute
      top:195px
      bottom:46px
      width:100%
      background:#fff
      overflow:hidden
      .menu-wrapper
        flex: 0 0 80px
        width: 80px
        background: #f3f5f7
        .menu-item
          display: table
          height: 54px
          width: 56px
          padding: 0 12px
          line-height: 14px
          &.current
            position: relative
            z-index: 10
            margin-top: -1px
            background: #fff
            color: $green
            font-weight: 700
        .text
          border-none()
        .icon
          display: inline-block
          vertical-align: top
          width: 12px
          height: 12px
          margin-right: 2px
          background-size: 12px 12px
          background-repeat: no-repeat
        .text
          display: table-cell
          width: 56px
          vertical-align: middle
          bottom-border-1px(rgba(7, 17, 27, 0.1))
          font-size: 12px
      .foods-wrapper
        flex: 1
        .title
          padding-left: 14px
          height: 26px
          line-height: 26px
          border-left: 2px solid #d9dde1
          font-size: 12px
          color: rgb(147, 153, 159)
          background: #f3f5f7
        .food-item
          display: flex
          margin: 18px
          padding-bottom: 18px
          bottom-border-1px(rgba(7, 17, 27, 0.1))
          &:last-child
          border-none()
          margin-bottom: 0
          .icon
            flex: 0 0 57px
            margin-right: 10px
          .content
            flex: 1
          .name
            margin: 2px 0 8px 0
            height: 14px
            line-height: 14px
            font-size: 14px
            color: rgb(7, 17, 27)
          .desc, .extra
            line-height: 10px
            font-size: 10px
            color: rgb(147, 153, 159)
          .desc
            line-height: 12px
            margin-bottom: 8px
          .extra
          .count
            margin-right: 12px
          .price
            font-weight: 700
            line-height: 24px
          .now
            margin-right: 8px
            font-size: 14px
            color: rgb(240, 20, 20)
          .old
            text-decoration: line-through
            font-size: 10px
            color: rgb(147, 153, 159)
          .cartcontrol-wrapper
            position: absolute
            right: 0
            bottom: 12px
  </style>

